LONG BEACH, CA—Thursday afternoon at the TED2013 conference got a little steamy. Christopher Ryan, a PhD of psychology and co-author of the book Sex at Dawn, sexed up the stage by talking about what he believes is the evolutionary nature of human sexuality. “Human beings are not descended from apes," he told the crowd. "We are apes. We’re [genetically] more closely related to chimps and bonobos than they are to any other primate.” As Ryan puts it, the question is “what kind of ape are we” in terms of our sexual natures? It turns out that we’re also closely related to chimps and bonobos in sexual practices—and the latter are famous for their sexual promiscuity and even “homosexuality.”

Consider that the average human has sex about 1,000 times per birth. According to Ryan, we share that number of sexual encounters with chimps and bonobos, but other primates are vastly different. Gorillas and all other primates typically have sex only 12 times per birth.

And, Ryan added, the frequency of sexual engagement is one reason humans, chimps, and bonobos have larger external testicles. Humorously comparing testicles to a beer fridge, Ryan noted that the idea is to be ready for a big party at any moment, with plenty to share. In other words, external testicles are all about frequent and spontaneous ejaculation.

What does this mean for human sexuality? Ryan argued that human sexuality evolved to function first and foremost as a bonding function, with reproduction being secondary (note this is sexuality, and not sex itself). This would mean that humans are indeed very similar to chimps and bonobos, which use sex for social purposes. Bonobos take socially driven sex to an extreme, in both hetero- and homosexual ways.

Ryan noted that the standard narrative of human sexuality is that men have bargained for women’s sexual functions by being providers/hunters, and women have complied as a result of this benefaction and protection. But the problem with this narrative, he suggested, is that the origin of human civilization doesn’t support this model. Before the advent of agriculture, we lived in hunter/gatherer societies that were fiercely egalitarian. Everything was shared.

Wouldn’t that include sexual relationships? Ryan says yes. Sexual exclusivity came later, after the advent of agriculture and more complex notions of property and exclusivity arose. But this development doesn’t change our nature. “Just because you have chosen to be a vegetarian,” he jokes, “doesn’t mean that bacon stops smelling good.” Just because we live in societies that generally organize around monogamous principles does not mean monogamy is the natural state of human sexuality. Like chimps and bonobos, it is natural for humans to have sexual desires for bonding.

In the end, Ryan argues that we must cease to conflate desires with property rights. We need to move beyond "men are from Mars and women are from Venus," he proclaimed to much applause. "The truth is that men are from Africa and women are from Africa.”

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As to the talk itself, it's interesting, and seems to match up with human history. We engage in monogamous relationships, and make them a central part of many of our societies, but promiscuity abounds.

And, Ryan added, the frequency of sexual engagement is one reason humans, chimps, and bonobos have external testicles. Humorlessly comparing testicles to a beer fridge, Ryan noted that the idea is to be ready for a big party at any moment with plenty to share. In other words, external testicles are all about frequent and spontaneous ejaculation.

Um, and by "humans, chimps and bonobos" you mean "all mammals" right? Because that's true of all mammals (possibly minus a few exceptions).

No, he was pretty clear on that. Checking with some searches, it does appear that most mammals do not have external testes. However, I did leave out the other qualifying condition, which is that in these primates, the testes are particularly large. Will update soon.

And, Ryan added, the frequency of sexual engagement is one reason humans, chimps, and bonobos have external testicles. Humorlessly comparing testicles to a beer fridge, Ryan noted that the idea is to be ready for a big party at any moment with plenty to share. In other words, external testicles are all about frequent and spontaneous ejaculation.

Um, and by "humans, chimps and bonobos" you mean "all mammals" right? Because that's true of all mammals (possibly minus a few exceptions).

No. There are things like testicle size and the shape of the penis head which are indicators of promiscuity. Large testicles to produce lots of sperm and/or a penis head designed to scrap out previously deposited sperm, are indicators of promiscuity. Across the mammal world there is an incredible variety of penises and testicles. Humans have big balls and a scraping penis head. Therefore it is likely we have been promiscuous for a long time.

You either live by God's laws or you live by the laws of the jungle...

Ahhh, the trusty old false choice. I hope you're enjoying your short-lived trolling today. I'm here to tell you that your cult has no future. Enough of us have woken up and moved on, vowing to never again be so embarrassingly thoughtless, and to pass on the good news of reason and logic to our loved ones. But by all means proselytize away, we know you're not really interested in anything about us.

Funny how when you make us out to be nothing more than an evolution of apes morality goes subjective... No set standard... Just do as you... Live as you wish... The biggest Satanist of all time Aliester Crowley said "Do What Thou Wilt, Shall Be The Whole Of The Law!" The only reason this country has survived this long and has been blessed to this extent is because the founding father's honored God's laws... So now since we're systematically removing them we're beginning to see the fruit of our stupidity... How many more kids and theaters goers are gonna have to pay before we humble ourselves to the point of saying "Ya know? Maybe God does exist... Maybe he did create us and told us to value our life... Maybe there is something to God's laws after all?" Then we wonder how these shooting happens... You take out the fundamental foundation of morality founded upon absolute love and we're beginning to see the fruit... You either live by God's laws or you live by the laws of the jungle... I can't wait until the aliens (fallen angels) come down and show you all video tape footage of them creating us by way of apes, there-by taking credit for our creation... I'm gonna laugh my butt off! Cause I know Jesus Christ is real and I am quite the honey-badger when it comes to how you feel about him...

You're wrong in several ways:

1- your founding fathers were not very religious, not all of them. ("lighthouses better than churches", and so on...)2- you can't at the same time credit your country successes to god, and pawn off its problems to something else. unless you prove causality, which you don't.3- lotsa countries with a lot less religion than you believe yours has, or different religions, or no religion at all, have been / are being very successful, too. again, you need to prove causality.4- ethics and morality do not require religion, and, reciprocally, religion implies neither ethics nor morality (as has been amply proven)5- you need to be clear about what your religion implies and means. your holy book says: no divorce, no shellfish, no dressing with 2 different cloths, no sex outside of marriage, and a bunch of other things... at what point of taking shortcuts does one no longer conform to the religion ? which points of the bible should be updated or corrected ?

If you're using birth control. Before the advent of birth control fertility rates were much higher. http://eh.net/encyclopedia/article/haines.demographyshows that in 1800, there were about 1348 children age 0-4 per 1000 women age 20-44. So on average, women were popping out babies at a rate of about 270 per thousand women per year, or to put it another way, it was on average a woman had a baby every 3.7 years throughout her period of fertility. (Heaven knows why they didn't count girls age 15-19 as they must have accounted for a number of babies.) So if women were having sex 1000 times per baby born that would be 1000 times per 3.7 years or once every 1.35 days. If we count the 5 days per 28 when a woman is having her period as unlikely days for her to be having sex, that means that on the other 23 days, she must be having sex 1.1 times per day to keep up her 1000:1 rate.

Um, and by "humans, chimps and bonobos" you mean "all mammals" right? Because that's true of all mammals (possibly minus a few exceptions).

No, he was pretty clear on that. Checking with some searches, it does appear that most mammals do not have external testes. However, I did leave out the other qualifying condition, which is that in these primates, the testes are particularly large. Will update soon.

Dogs are naturally promiscuous and have external testes. Wolves are naturally not promiscuous and have external testes.

Thinking about it, how many mammals are there that are not naturally promiscuous? What would "promiscous" even mean with respect to most mammals, since formation of monogamous bonds are quite unusual in mammals? Most mammals mate opportunistically. Humans are on the spectrum between opportunistic maters and bonded maters.

If you're using birth control. Before the advent of birth control fertility rates were much higher. http://eh.net/encyclopedia/article/haines.demographyshows that in 1800, there were about 1348 children age 0-4 per 1000 women age 20-44. So on average, women were popping out babies at a rate of about 270 per thousand women per year, or to put it another way, it was on average a woman had a baby every 3.7 years throughout her period of fertility. (Heaven knows why they didn't count girls age 15-19 as they must have accounted for a number of babies.) So if women were having sex 1000 times per baby born that would be 1000 times per 3.7 years or once every 1.35 days. If we count the 5 days per 28 when a woman is having her period as unlikely days for her to be having sex, that means that on the other 23 days, she must be having sex 1.1 times per day to keep up her 1000:1 rate.

For 24 years.

I don't think so.

You clearly do not get it. The dude has a PhD in psychology. With that he is uniquely qualified to speak with absolute certainty on the following matters:

1. Exactly how human pre-agricultural societies lived; I mean right down to their exact mating habits

2. To speak authoritatively about genetics. His extensive genetics expertise allows him to classify us, without any doubt, as simply another ape.